Working with the idea that commercial and small-batch coffee roasters are able to produce drinkable coffee despite using vastly different methods, researchers in New Zealand are exploring automated coffee roasting. The project is being led by Waikato University engineering PhD candidate Cameron Kelly and professor Jonathan Scott.

“If you ask people how much they spend on gasoline and how much they spend on coffee, coffee is the second-largest dollar volume commodity traded on the surface of the Earth, right after fossil fuel. Currently, roasting machines require skilled operators and the roasting process adds substantially to the cost of the beans. So you need only a little leverage to make money here,” Scott told the Waikato Times.

According to Scott, the researchers are fully aware of the primary impedance to automated coffee roasting. “The timing of the different stages depends on the source of the beans, how big they are, and how thoroughly they have been dried,” he told the paper. “If you were to discover that having a certain amount of heat for a certain period of time gets you a great cup of coffee this week, you may not get the same result next week, because something’s changed.”

Part of the thinking behind the project — which involves an infrared camera to pinpoint roast temperatures as well as a system that involves heated air blowing up through the cylinder providing the tumbling force, rather than a horizontally tumbling roaster — is that temperature ought to be able to be controlled enough to at least produce a decent cup of coffee.

“The domestic aficionado likes the smell but the commercial guys don’t get that because health and safety requires them to vent their systems outdoors,” Scott says. “There’s a lot of divided opinion and hearsay but it all makes you feel that if there are so many different ways and they’re all generating drinkable coffee, it ought to be possible to automate it.”